Randeep Agarwal, The University of Queensland

SMALL SCALE LNG: A SPEEDY SOLUTION FOR CLEANER COOKING FOR MILLIONS

Authors - Randeep Agarwal1, Sanjay Rastogi2, Hongjun Fan3, Upinder Kumar4, Jaiganesh Dakshinamurthy5, Dr Chris Greig6

1Adjunct Associate Professor, The University of Queensland; 2Vice President (Technical) Petronet LNG India; 3Senior Engineer, Wuhan research and rules institute, China classification society; 4Chief Manager Technical, Petronet LNG India; 5Manager Technical Services, Petronet LNG India. Professor, the University of Queensland.

Abstract Globally, there are approximately 1.4 billion people without access to electricity and 2.7 billion people who rely on solid fuel (wood, crop residue, dung and coal) for cooking. The use of these traditional cooking fuels creates several significant problems, including deforestation, with a resultant loss of biodiversity and the elimination of carbon sinks which could offset global warming. There are also serious consequences for health and wellbeing. In 2012, indoor air pollution arising from the use of traditional cooking fuels was the cause of more than 4.3 million premature deaths, more than 60% of which were women and children.

There is ample evidence of the health benefits associated with the use of liquefied petroleum gas (LPG) as a cleaner cooking fuel. In this context, various governments, including China, India, Guatemala, Indonesia, Kenya, Pakistan, Sri Lanka, Albania, Brazil, Mexico and Peru, have instituted programs aimed at replacing solid fuels with liquefied petroleum gas (LPG) and together represents approximately 45% of the world population. However, affordability has proven to be a critical consideration in adoption of LPG as a cooking fuel prompting the governments to encourage LPG uptake through subsidies. This paper explores the opportunity for clean cooking needs to be fuelled by natural gas and specifically imported LNG. Current practice of using high pressure pipelines for natural gas transmission and distribution is plagued by lengthy delays (sometimes between 5 to 7 years) and large cost overruns due to regulations, litigation, financing and social issues, many of which appear intractable. A new approach to gas distribution is discussed i.e. Small-scale LNG technology deployed at a macro scale in urban and rural communities. The low-pressure gas pipeline networks could be installed with relative ease and thousands of kilometres could be connected within 1 to 2 years. The paper will discuss concept engineering, high level economics of cost of cooking fuels (affordability), project schedule, speed and scale potential and the environmental benefits.

2. Introduction

The use of solid fuels for cooking is a significant health issue; World health organization (WHO) reporting an estimated ~4.3 million premature deaths/year in 2012, associated with inhalation of carbon monoxide and particulate matter from biomass cooking, primarily among women and children [1]. This has led many organisations to call for an end to the use of solid cooking fuels, including for example, the Clean Cooking Alliance [10], an initiative of the UN foundation, which set a target in the year 2010 of ~200 million people having access to clean cooking by 2020. The International energy agency (IEA) Access 2017 report [2] concluded that efforts to promote electricity access are having a positive impact in all regions, and the pace of progress has significantly accelerated. The number of people without access to electricity fell to below 1.1 billion (from 1.4 billion) people for the first time in 2016, with nearly 1.2 billion people having gained access since 2000. However, the same report indicated that progress in clean cooking access is not keeping pace. Today, an estimated 2.8 billion do not have access to clean cooking facilities. A third of the world’s population – 2.7 billion people – rely on the traditional use of solid biomass to cook their meals. Around 120 million people use kerosene and 170 million use coal. The rural poor in developing nations are most affected. The key reasons for the slower progress cited in this report; low consumer awareness, financing gaps, slow technological progress and lack of infrastructure for fuel production and distribution. Sub-Saharan Africa is the region showing the least progress on clean cooking. Almost 80% of the population still cooks with solid biomass, a share that has declined by just three percentage points since 2000. Population growth means that, despite this small percentage decline, the number of people still cooking with solid biomass has increased by 240 million to reach around 780 million. Figure 1 illustrates the population gaining access to clean cooking and population growth by regions highlighting the lack of progress.

Figure1: IEA trends on population without access to clean cooking Sourced from the IEA web resources [2]

A recent publication titled, ‘Tracking Sustainable Development Goal (SDG) 7: The Energy Progress Report,’ released during the 4th Sustainable Energy for All Forum(SE4ALL), shows that global progress is too slow to achieve access to affordable, reliable, sustainable and modern energy for all by the UN target of 2030[4]. The trends are particularly concerning regarding energy access and clean cooking fuels, whereas progress on energy efficiency and renewable electricity is accelerating. Although access to clean cooking has outpaced population growth in parts of Asia, driven largely by widespread dissemination of LPG in the cities and the rural regions or piped natural gas in the cities. The population growth in Sub-Saharan Africa has surpassed the number of people gaining access to clean cooking technologies by a ratio of four to one [5]. While progress is being made in India and China, the absolute populations continuing to cook with solid fuels remains enormous particularly in India where the number remains above 850 million. SE4All published a global heat map on millions of people without access to clean cooking (Figure 2).

Figure 2: Heat map on people without access to clean cooking Sourced from web resources of SE4ALL [11] IEA projections depicted in Figure 2 indicate that at the current trajectory, 2.3 billion people will still be using traditional cooking methods in 2030 [3]. There are also huge disparities between urban areas, where 83% of the population has access to clean cooking, and rural areas, where access is only 32%.[6]. An amply clear signal that new technologies and infrastructure need to be developed to create an accelerated access for the rural regions. The challenge is exacerbated by population growth. The UN report [7] projects that the world population in 2050 ~could reach circa 9.8 billion which is an addition of nearly ~2.2 billion people to the current population of ~about 7.6 billion; a growth of ~around 70 million people per annum on average, with much of the growth anticipated for rural areas[7]

Figure 3: IEA projections on population without access to clean cooking Sourced from web resources of clean cooking alliance [10] The evidence suggests that implementation of cleaner cooking options is not keeping pace with population growth with profound implications for the health and well-being of billions of people in developing nations, and resulting in

significant environmental harm. It is expected that the renewable technologies and/or solar powered induction heating may reach millions of rural populations by ~2040 to 2050. Therefore, cleaner cooking options, for rural regions in the developing countries, need focus during a transition phase ~2020 to 2050. Industry reports indicate that the natural gas and LNG are in abundance specifically the LNG liquefaction and regasification infrastructure has grown significantly over the last decade or so and the LNG supply position is expected to remain strong [16]. In this paper we explore an innovative approach to deploying natural gas for cooking in rural areas of developing nations, which could take advantage of growing LNG supplies and overcome the problems associated with solid-fuel cooking. A concept involving small-scale LNG (SSLNG) together with innovative gas distribution networks may offer a potential solution, which could be more rapidly deployed at scale than traditional approaches.

3. Small scale LNG (SSLNG) for domestic cooking – a conceptual model

Natural gas accounts for nearly 25% of global energy demand, and nearly half of that is converted to LNG for at least part of its journey to the end user [8]. Industry experiences suggest that SSLNG is an emerging model within the LNG value chain, and although, currently in evolutionary stages but is expected by some to have considerable impact on future demand profiles for LNG & gas, worldwide. Many small users of LNG have surfaced in industrial, transport (shipping & road), domestic gas and power generation sectors. The gas industry association, International Gas Union (IGU) categorises, the facilities handling less than 1 Million tons per annum (Mtpa) as SSLNG and SSLNG carriers are defined as vessels with a LNG storage capacity of less than 30,000 cubic metres [9]. However, recent industry experiences show that the term SSLNG is being interpreted in several different ways e.g.

A. Small scale liquefaction;

B. Small scale re gasification terminals; and/or

C. Small scale distributed LNG (dLNG) in trailers or in cylinders

The term LNG trucks are often misinterpreted by trucks fuelled by LNG to replace diesel and, therefore, limiting the discussion to LNG fuelled vehicles only. An alternative of trucked LNG could facilitate the distribution and supply of natural gas to users. We propose the term distributed LNG (dLNG) may be used to distinguish between emerging applications of SSLNG. Based on recent industry experiences, dLNG could be further split in many sub categories and scales;

(i) Fuelling stations to replace diesel in the vehicles (~10 to 60 m3)

(ii) Cylinders for small and/or micro industrial and commercial users (~0.5 to 1 m3)

(iii) Trailers to small industrial and commercial users (~1 to 20 m3)

(iv) Trailers to feed small gas fired power generators (~10 to 60 m3)

(v) Shipping fuel supplied by trailers (~100 to 200 m3/ hr filling rate)

(vi) Trailers to feed natural gas for domestic use (~10 to 60 m3)

In China, dLNG is prominent in the industrial sector users like ceramics, glass, paper, metal smelting and some standalone consumers of steam, heat or power such as hotels, hospitals and commercial buildings. In transport sector the heavy trucks and buses are new users of LNG as a fuel to replace diesel. Recently, the International maritime organization (IMO) has set a new limit by restricting Sulfur to 0.5% in fuel oil from 1 January 2020 from current limit of 3.5%, paving the way for LNG as a new shipping fuel [11]. Recently cylinders are also being used to supply LNG in very small quantities to micro industrial or commercial users. This paper is limits its focus on distributed LNG for cleaner cooking (sub category vi, above). This value chain is termed as dLNG-CC hereinafter in this paper. Fig 4a & 4b show a conventional LNG value chain and an evolving dLNG-CC value chain respectively. Natural gas can be sourced either domestically or via regasified LNG.. Fig 4a depicts a conventional value chain where the domestic gas or regasified LNG is usually supplied via a large network of high pressure pipelines. The literature [nn] shows that widespread implementation of city gas distribution (CGD) has not achieved the desired scale as quickly as planned because the current piped natural gas distribution model is dependent on an expensive high-pressure gas pipeline networks. Numerous new pipeline projects are underway but most are plagued by lengthy delays and large cost overruns due to regulation, litigation, financing and social issues, many of which appear intractable. Whereas, several SSLNG projects have been implemented within 1 to 2 year timeframes, however, dLNG . Figure 4b depicts dLNG-CC value chain where, liquid LNG is transferred directly into 20 ton trailers and supplied to gas distribution networks. In this value chain the high-pressure steel pipelines are not required.

Figure 5 illustrates shows a new concept of involving nodal gas distribution. This gas distribution model will consist of a ring main and multiple radial supply nodes; all constructed using low pressure pipelines. The total system has been termed a “cluster”. The LNG boil off pressures may be sufficient to distribute gas to large distances without the need of pump or compression; a hydraulic model was run using the software Piper

TM. Following that analysis a process simulation

model was run using PROII. Both these software’s are well recognised industry standards, globally. The input assumptions used for the hydraulic/process modelling; LNG storage pressure ~550 kPa

Gas supply pressure @exit of AAV ~500 kPa

No. of radial nodes ~14

No. of houses@ each node ~1000

No. of residents per household ~5

Gas consumption per household ~20 m3 per month

Capacity factor for the pipeline ~1.5 (i.e. max capacity 30 m3 per month)

Gas required @ each node ~20000 m3 per month

Total gas required for one cluster ~280000 m3 per month

Delivery pressure @ exit of each node ~40 kPa

The model outputs are; Distance achievable ~20 kms (radial)

Distance achievable ~40 kms (dia.)

Pipeline sizes ~2” to 6”

Total pipeline length for one cluster ~300 kms

LNG volume required ~550 m3 per month

LNG volume per day ~20 m3

Therefore, for this cluster, the population reachable is ~70,000 (14*1000*5) and only one LNG trailer of ~20 m3

capacity, per day, is enough to deliver the required cooking fuel. An extrapolation using a pipeline capacity factor (1.5) will allow gas supply to ~100000 people with one LNG truck of ~30 m

3 per day.

The reachable area for this cluster (40 Km diameter) is ~1250 sq.km; population density of ~80 people/ sq.km (=100000/ 1250). However, the typical population density in the concerned rural regions is between ~100 to ~400 people per sq. km; a 40 Km diametric cluster could have up to ~500000 users (calculated for a population density of ~400). Therefore, the scale could be achieved either by larger size cluster and/or multiple clusters. The most versatile pipeline material being polyethylene (PE); PE pipe systems are designed for 50 year service life based on empirical and actual test data but under normal operating conditions the actual life is expected to be considerably greater[12].

Due to the pressurised LNG trailers and storage, the boil off can be contained within the vessels, without zero emissions to the atmosphere, for weeks.

Figure 5: One Cluster, dLNG-CC value chain (not to scale)

4. Scale & Speed potential

The above cluster is designed with a scale factor of five(5) to supply up to ~500000 people, only five 30 m3 LNG

trailers per day will be required; that is equivalent to ~60 tons per day or ~0.022 million tons per annum (Mtpa) of LNG. In one or more given regions, if 100 such clusters are developed, ~50 million rural population (10 million households) will be able to access the cleaner cooking fuel. In this case, only ~2.2 Mtpa of LNG would be required. Based on the assumptions, for a scaled model for 50 million people, the infrastructure requirements may be; 1) 500 LNG trailers each of 30 m

3 capacity, 2) ~200 LNG storage vessels, 3) ~200 Ambient air vaporizers 4) 30,000 kms

of low pressure piping 5) Metering and associated instrumentation 6) ~10 million gas cook stoves. However, the numbers and the quantity may vary depending on logistics design and management. From an ease of execution perspective, each country may consider 10 such clusters spread over ~10 states or provinces; within the country each state or province need to develop only ~1 cluster. The central node can be a city/ 2

nd tier city with a good road access. The schedule will enable access to 5 million users by each country and a

target of ~50 million users within ~3 years may be achievable. An initial period of ~3 years also enables capacity building for this intervention. It is also assumed that further replication and scaling up then becomes a business as usual case and a global target of access to ~500 million users by 2024 seems feasible. The creation of dLNG-CC infrastructure for cleaner cooking may generate additional LNG demand of ~22 Mtpa or more, globally. Industry experiences suggest that installation of PE distribution piping is relatively easier than the HP steel transmission pipelines. 5. Economics and affordability

The fossil fuel based “cleaner” model is based either on LPG for cities and rural regions and/ or piped natural gas in cities. LPG is sold in cylinders by weight (kilograms, kg) while natural gas is sold by volume (standard cubic meters, s.cu.m) and LNG is traded in heat value i.e. Million British thermal units (MMBtu) or Gigajoule (GJ). Both the units are roughly the same.

LNG Storage Vessel Ambient air

vaporizer

LNG trailer

Central Node

@ SSLNG site

Distribution Node 1

~3” PE pipe

~design 30 m3/month (gas)

40 kms

For example, in case of India, a non-subsidised LPG cylinder (14.2 kgs) costs around Rupees 800 (~ $12) and lasts for ~30 days for a family of five; approximately 12 cylinders per year. In other words, the LPG in heat value terms is costing ~$16 per GJ. But the locally sourced natural gas costs around 27 Rupees (40 US cents) per s.cu.m. Natural gas consumption for a household with 5 people is anticipated to be ~18 s.cu.m. per month (equivalent to one LPG cylinder in terms of heat value equivalence) so the monthly cooking fuel bill would be 480 Rupees (~ $7). The cost, to the consumer, in heat value terms is ~$10 per GJ. Therefore, the local piped natural gas costs ~35% cheaper than LPG. For a dLNG-CC value chain, if the landed cost of LNG is ~$9 per GJ, and a margin of ~$1 per GJ for development of a new distribution infrastructure and operating costs of $1 per GJ i.e. non subsidised natural gas can be supplied at ~$11 per GJ which is still ~$5 per GJ cheaper than non-subsidised LPG. A margin of ~$5 per GJ is attractive enough to offset government subsidies and commercial viability for LNG/gas distributors and retailers for dLNG-CC development. India has an ambitious program to supply more than 100 cities with piped natural gas to the affluent and middle classes while the rural poor are on the LPG program; urban populations pay only ~$10 per GJ for cooking fuel (city gas) and the rural poor pay ~$13 per GJ ( LPG with 20% subsidy). The questions which need to be addressed are; 1) why the rural poor should not have access to cheaper cooking fuel comparable to urban populations ? 2) The cost of local natural gas and dLNG-CC, even without subsidies, is cheaper than the subsidised LPG. Why governments should not remove high subsidy burdens by promoting gas and/or dLNG-CC for the rural regions? 3) Why governments should not redirect the subsidy budgets to develop dLNG-CC infrastructure? 6. Climate, Pollution, Environment and Safety

Natural gas is considered to be the cleanest, safest and most affordable fossil fuel. LPG has two origins: approximately 60% is recovered during the extraction of natural gas and oil from the earth, and the remaining 40% is produced during the refining of crude oil. Natural gas is less carbon intensive than LPG. Natural gas emits 10 to 20 percent less carbon dioxide (CO2) when combusted compared with emissions from a typical new coal plant [9, 10]. The combustion of natural gas does not emit soot, dust or fumes and almost no environmentally damaging sulphur dioxide (SO2) emission. The LNG supply trucks are usually fuelled by LNG/ gas or diesel; increasingly on LNG in the recent times. Conversely, to distribute LPG cylinders to 10 million households (50 million people), ~50000 trucks, usually run on diesel, are needed. In case of dLNG-CC only ~500 LNG trailers may be required to feed the same population. Therefore, dLNG-CC value chain will not require large road infrastructure as compared with LPG. Any impact of future carbon price has not been included in the cost estimates, however, will need to be considered in the detailed economics. Also any environmental impact of large PE networks execution need to be assessed, however, a presumption is that these will be relatively minor as compared with HP steel pipelines. Natural gas is safer than LPG. Natural gas is lighter than air while propane is heavier than air. This is important in the event of a leak because natural gas will simply float away while propane will collect near the ground or near the floor of a home. If a match was to be lit or a spark was to fall near exposed propane, it would create an explosion that could hurt or kill anyone close to it. 7. Longevity of the dLNG-CC infrastructure As with all fossil fuels, natural gas reserves are limited, and while the production of gas/LNG is generally considered yet to peak, depletion is expected during the coming decades. There are many scenarios and models analysed to predict peak and depletion of natural gas, but for the purpose of this discussion, it is assumed that abundance of natural gas will definitely exist till the year 2050.Therefore, research and innovation is currently on to make rapid transition to renewable and clean energy options. Therefore, a pertinent question, at this point in time, to address is the longevity of dLNG-CC infrastructure and whether the capital expenditure on dLNG-CC is a wasteful exercise. In the context of the clean or cleaner cooking a number of options in the pipeline are; 1) Clean cooking stoves using biomass, 2) LPG, 3) Natural gas, 4) Biogas (renewable gases), 5) Hydrogen 6) Solar power in conjunction with induction heaters. The option 1 and 2, above, are being currently pursued for both urban and rural users while the option 3 (natural gas), in most cases, is available to the urban users only. The options 4, 5 and 6 are potential options for the future, however, the speed and scale attractiveness is still under investigation. While the proposed dLNG-CC model helps to enhance natural gas usage for the rural communities, at a desired speed and scale, it can still be used for options of the future i.e. option 4 & 5. The option 6 is not being evaluated in this paper but clearly remains a competing option with dLNG-CC, however, speed, scale and affordability potential still need to be investigated. The PE pipe materials are considered most suitable for transporting biogases [13]. Therefore, the low pressure PE networks, initially developed for dLNG-CC, can still be used for renewable gases, with an expected life of more

than 50 years, usually up to ~100 years. Also, the PE natural gas networks have been tested on hydrogen in Denmark and the results are extremely positive [14]. In addition, the PE networks can also be used for water and sanitation purposes for additional 50 years, post cessation of gas supplies. Figure 5 below shows that PE pipeline infrastructure which can be repurposed for other usages into the future i.e. biogas (renewable gases), hydrogen and/or water. The “future proofing” of capital expenditure on energy infrastructure should be a catalyst from an energy policy and planning perspective. Same benefits cannot be claimed for the high pressure pipeline networks.

Figure 5: Longevity of PE distribution networks Therefore, the capital expenditure for the low pressure infrastructure could be discounted over 50 years or more. The cryogenic trailers and the pressure vessels can also be used for the cold chain infrastructure for food into the future. 8. Alignment with the International Solar Alliance (ISA) program Many of the concerned countries (Asia, Sub Saharan Africa and the Pacific Islands) have already joined and/or intend to join the international solar alliance (ISA). The dLNG-CC infrastructure specifically the PE distribution networks is expected to enable accelerated implementation of solar technologies i.e. solar assisted Biogas (renewable gases) production, hydrogen production thru electrolysis using solar power and/or solar pumping for water. In these scenarios, the PE network can be repurposed for efficient distribution of renewable fuels and water (Figure 5). More importantly, the PE networks will enable development and utilization of decentralised solar technologies. In addition, availability of natural gas is also an opportunity generate micro scale power to complement the intermittency of solar power. 9. Future scenario: High pressure pipelines are built If and when the high pressure pipelines are constructed, the dLNG-CC infrastructure (i.e. trailers, storage vessels and vaporizers etc.) can still be utilized as “peak shaving”. An opportunity to minimize the capital expenditure (Capex) for HP steel pipelines if peak shaving capacity is already in existence.

Water

Biogas Hydrogen

Conclusions & Recommendations dLNG-CC offers a potentially feasible supply chain for cleaner cooking and can emerge as an alternative and/or complimentary alternative to current cooking fuels such as LPG. dLNG-CC is likely to have better affordability than LPG. dLNG-CC has the potential to be scaled-up more rapidly than traditional natural gas supply infrastructure and could accelerate access to cleaner cooking solutions in rural areas of developing nations. Natural gas is the cleanest fossil fuel and offering reduced air pollution and lower GHG emissions during production, transport and combustion. The GHG emissions benefit, however, is subject to the gas leaks being minimal because natural gas (primarily methane) has large global warming potential (23 times of CO2). In the context of cleaner cooking fuels, the PE networks can become a lifelong “backbone” infrastructure for future renewable gases (biogas, hydrogen etc.). PE network and LNG vaporization design innovations will emerge for operational flexibility and efficiency. Consumption of cooking gas is assumed to be 20 m

3 per month per household, resulting in ~22 Mtpa of LNG

demand which is a very small amount of the total liquefaction and LNG receiving terminal capacity, globally [16]. A transition period of 2020 to 2040 could be implemented. Further research should be pursued to better understand the non-technical aspects for accelerated project execution i.e. political, administrative, regulatory, financial, retailing, marketing, social, and cultural and consumer behaviours. Because it is often these factors which are constraints for successful execution of technical solutions. National energy policy and planning should be reviewed in the context of dLNG-CC priorities and in light of its complementarity to other cooking fuel options during the transition period. Similarly, the international and national financing agencies (World Bank, Asian Development Bank, Asian Infrastructure Investment Bank etc.) should examine dLNG-CC supply chain. dLNG –CC value chain may have also other spin offs. For example, there are many stranded natural gas fields in the world with limited reserves which are not economically feasible to develop. The dLNG infrastructure will enable local (in country) liquefaction and distribution of LNG. Also the inherent low temperature of LNG is available free and may help cold chains for produce and food processing without large investments in energy hungry refrigeration systems. Some reports suggest that ~15 billion USD agricultural produce is wasted in India every year due to lack of cold chains. In addition to countries in Asia and sub-Saharan Africa, the feasibility of dLNG-CC for the pacific islands should also be examined. Acknowledgements We wish to acknowledge Chetan Choudhari, Senior Facilities Engineer, Origin Energy for the hydraulic modelling work on PE distribution network. I also wish to acknowledge Australia Pacific LNG and Gas Energy Association (GEA, Australia) for their support and encouragement.

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